Apparatus for producing surfaces of revolution eccentric to one another



A. H. DALL March 12, BOSE. I

APPARATUS FOR PRODUCING SURFACES OF REVOLUTION ECCENTRIC TO ONE ANOTHERFiled July 28, 1955 2 Sheets-She s; 1

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March 12, 1935. A. A 31,993,831

APPARATUS FOR PRODUCING SURFACES OF REVOLUTION ECQENTRIC TO ONE ANOTHERFiled July ,28, I933 2 Sheets-Sheet 2 Patented Mar. 12, 1935 UNITEDSTATES PATENT OFFICE APPARATUS FOR PRODUCING SURFACES OF REVOLUTIONECCENTRIC TO ONE ANOTHER Albert H. Dali, Cincinnati, Ohio, assignor toCin cinnati Grinders Incorporated, Cincinnati,

This invention relates to improvements in machine tool structures,particularly grinding machines, and to an improved method for producingarcuate surfaces eccentric to one another.

One of the principal objects of the present invention is therefore theprovision of an improved method and improved apparatus for producing asurface of revolution eccentric to a preformed surface of revolution.

Another object of the invention is the provision of an improved methodand apparatus for grind-'- ing an exterior surface of revolution about acenter laterally spaced with respect to the center of a previouslyformed internal surface of revolution.

A further and specific object of the invention is the provision of animproved method and apparatus for grinding the arcuate contact face ofthe lug on rocking shoe journal bearings in definite predeterminedrelation to the arcuate hearing face of the said segmental rockingbearing shoes.

Other objects and advantages of the present invention should be readilyapparent by reference to the following specification, considered inconjunction with the accompanying drawings forming a part thereof and itis to be understood that any modifications may be made in the exactstructural details there shown and described, within the scope of theappended claims, without departing from or exceeding the spirit of theinvention.

In the drawings:

Figure 1 is a front elevation of a grinding machine for carrying forwardthe improved method and showing the improved apparatus in place.

Figure 2 is a sectional view taken on the line 2-2 of Figure 1.

Figure 3 is a sectional view taken on line 3--3 of Figure 2.

Figure 4 is an elevational view of a portion of the work supportingmandrel as seen from line 4-4 on Figure 3.

Figure 5 is a perspective view of a segmental rocking bearing shoe,illustrating one type of work adapted to be finished by improved methodand apparatus of this invention.

Throughout the several views of the drawings similar referencecharacters are employed to denote the same or similar parts.

As was noted above, this invention pertains to an improved method andapparatus for producing arcuate surfaces of revolution eccentric to apreviously formed surface. One type of work adapted to be finished bythis improved method and apparatus is the rocking bearing shoe shown inFigure 5, and it is deemed expedient if a description thereof be givenin order to more fully understand the invention. The rocker bearing shoe10, therefore, comprises an arcuate bearing face 11 5 which is formed toa radius substantially equal to that of the spindle or shaft journalwith which it is to be used. The shoe 10 is of a length substantiallyequal to the length of the journal which it is adapted to support. Onthe back face 12 of 10 the shoe it is provided with a lug 13 having itsouter surface arcuately shaped or rounded as indicated at 14. Therounded portion 14 is generated about an axis that is spaced from theaxis of the bearing face 11.

' The shoes when placed in use are disposed within a bore in the spindleor shaft housing, which bore is formed substantially concentric with thebearing face 11 from which it follows that the radius at the surface 14is different from '20 the radius of the bore. As a matter of fact, theradius of the arcuate or bearing surface 14 is less than the radius ofthe bore in which the shoes are disposed, but this radius is greaterthan the radius of the contact or bearing face 11. In order to finishthe surface 14 it is desirable to rotate the shoe 10 about an axis whileadjacent to a tool or grinding wheel. At the same time the shoes cannotbe rotated about the axis of the hearing face 11 since this wouldproduce the surface 14 as concentric with the said face 11.

Resort was therefore had to a supporting mandrel 15 to which is secureda plurality of the shoes which are simultaneously operated upon. Thismandrel 15 was provided adjacent each end with a plurality ofcircumferentially spaced pins 16 and 17 which pins are individually inalignment with one another to provide spaces or portions 18', 19, 20',21', 22' and 23 between them, each of which supporting portions isadapted to receive a work piece or segmental shoe 10. Each supportingportion of the mandrel is formed about its own axis or center, such as18, 19, 20, 21, 22 and 23 and of a radius equal to the radius of thebearing face 11 of the work. It is to be understood that the supportingportion l8-is formed about the axis or center 18, supporting portion 19'about the axis or center 19, etc. By this construction the normal axis24, or the axis of the mass of the mandrel, became the axis about whichthe arcuate contact face 14 was to be formed and this axis 24 is equallyspaced from each of the other axes 18 to 23 inclusive. By reference toFigure 2, it will be noted that the axis 24 and each of the other axesare respectively in line with the center of the work supporting portionbetween adjacent pins 16 and 17. It will also be noted that the mandrel15 is provided with a plurality of arcuate seats, each being disposedbetween adjacent pins 16 and 17 and each adapted to receive a workpiece.

In order to hold the shoes on the mandrel during the operation on thelugs 13yfor the formation of the contact surfaces 14 there is provided apair of rings 25 and 26, which encircle the mandrel and work on oppositeends of the lugs 13. The rings 25 and 26 respectively carry workclamping screws 27 and 28, there being as many clamping screws as thereare work pieces finished at one setting, here shown as 6 in number.Therefore, after the workpieces have been mounted on their respectivemandrel supporting seats, the rings are placed over the work and mandreland the clamping screws drawn home. The entire assembly is then placedin a machine tool and rotated about the axis 24 and a tool brought intoposition for engagement with the ribs 13 of the work.

Figure 1 shows a center type grinding machine with the mandrel and thework mounted in position thereon. As there shown, the mandrel issupported by centers -29 and 30 respectively carried by the headstock 31and tailstock 32. The said head and tailstocks are in turn secured to awork supporting table 33 mounted on suitable guide ways'provided by abed or support 34.

The bed 34 supports the usual grinding wheel slide 35 having bearings 36formed thereon in which is disposed a spindle for the grinding wheel 37.In addition, the carriage 35 has secured to it a guard or lmusing 38which substantially encircles the grinding wheel 37 for confining thecoolant usual with grinding machines. Any suitable means may be providedfor effecting the rotation of the spindle and grinding wheel at theusual high grinding rate of speed.

In order to rotate the work while supported on the centers 29 and 30 theheadstock has associated therewith a face plate 39 from which projectsthe driving pin 40 that contacts with the work driving dog 41 secured tothe reduced extension 42 of the mandrel 15.

The tool slide 35 is adapted to be actuated laterally of the bed 34toward the work table 33 and any suitable means may be provided for thispurpose. As shown in the drawings, this means may comprise the usualcross feed mechanism which terminates in the hand wheel 43 andincremental power feed mechanism, the latter mechanism including, as iswell known, the ratchet 44 and pawl 45 operable by the rod '46 throughmechanism contained within the box 4'7.

The operation of the method and apparatus of the present invention is asfollows: The work pieces have the inner face 11 completely formed to aradius equal to the radius of the various supporting portions on themandrel l5, and then placed on the said mandrel and secured in operativeposition by the clamping rings 25 and .26 and their clamping screws 27and 28. This assembly is then placed .in a machine tool between opposedwork supporting centers whereupon the said assembly is rotated about theaxis 24 and a tool fed relative thereto.

What is claimed is: e

1. In a mechanism of the class described the combination with a bed, agrinding wheel rotatably mounted thereon, a work supporting tablemounted on the bed, opposed head and tail stocks supported by the worktable, a work carrying the mandrel, said arcuate face of the mandrelbeing adapted to receive a contragenerically formed face on a workpiece, clamping means for securing the work piece to this seat, andmeans associated with the head stock for rotating the mandrel and workpiece about the axis of the mandrel for thereby producing an arcuatesurface on the work piece eccentric to the previously formed arcuatesurface thereon.

2. In a grinding machine for producing work pieces having an arcuateface thereon generated about an axis eccentric to the axis of an arcuatesecond face on the work piece comprising a mandrel, the axis of which iscoincident with the axis of the arcuate face to be generated on the workpiece, the mandrel having formed thereon an arcuate seat generated aboutan axis eccentric to the axis of the mandrel and adapted to receive thesecond face on the work, clamping means for securing the work piece tothe arcuate seat on the mandrel, a grinding wheel mounted on the bed,and means for eifecting a relative rotation between the work andgrinding wheel.

3. In a grinding machine for producing work pieces having an arcuateface thereon generated about an axis eccentric to the axis of an arcuatesecond face on the work piece comprising a mandrel, the axis of which iscoincident with the axis of the arcuate face to be generated on the workpiece, the mandrel having formed thereon an arcuate seat generated aboutan axis eccentric to the axis of the mandrel and adapted to receive thesecond face on the work, clamping means for securing the work piece tothe arcuate seat on the mandrel, a grinding wheel mounted on the bed,means for effecting a relative rotation between the work and grindingwheel, and means for effecting a relative feed between the grindingwheel and work while said wheel and work are being rotated.

4. In a grinding machine for simultaneously producing a plurality ofwork pieces, each adapted to have an arcuate face generated thereonabout an axis eccentric to a previously formed arcuate surfacecomprising a rotatable grinding wheel, a work supporting mandreladjacent the grinding wheel and rotatable about the axis thereof, saidmandrel having formed thereon a plurality of arcuate seats each adaptedto receive the arcuate surface of the work piece, means carried by themandrel adjacent each end of the lateral edges of each arcuate seatthereon and between which the work is disposed for accuratelypositioning the work relative to the mandrel, and clamping means forsecuring the work pieces to the mandrel.

5. In a grinding machine for simultaneously producing a plurality ofwork pieces, each adapted to have an arcuate face generated thereonabout an axis eccentric to a previously formed arcuate surfacecomprising a rotatable grinding wheel, a work supporting mandreladjacent the grinding wheel and rotatable about the axis thereof, saidmandrel having formed thereon a plurality of arcuate seats each adaptedto receive the arcuate surface of the work piece, means carried by themandrel adjacent each end of the lateral edges of each arcuate seatthereon and between which the work is disposed for accuratelypositioning the work relative to the mandrel, and clamping means forsecuring the work pieces to the mandrel, comprising a clamping screw foreach end of the work for holding said ends of the work against themandrel seats.

6. In a grinding machine for simultaneously plurality of arcuate seatseach adapted to receive the arcuate surface of the work piece, meanscarried by the mandrel adjacent each end of the lateral edges of eacharcuate seat thereon and between which the work is disposed foraccurately positioning the work relative to the mandrel, means forsecuring the work pieces to the mandrel, comprising a clamping screw foreach end ofthe work for holding said ends of the work against themandrel seats, and a ring encircling the work and mandrel through whichthe clamping screws are axially adjustable.

7. A mandrel for supporting a plurality of segmental bearing shoes whilehaving the archate bearing face on the contact rib thereof formedcomprising a mandrel having formed thereon a plurality of arcuate seatseach generated about an independent axis eccentric to the axis of themandrel, means carried by the mandrel circumferentially thereof anddefining the lateral limits of the bearing shoe seats, said arcuateseats being coincident to the segmental shoes bearing surfaces, andmeans encircling the bearing shoes and mandrel for securing said shoesto the mandrel.

8. A mandrel for supporting a plurality of segmental bearing shoes whilehaving the arcuate bearing face on the contact rib thereof formedcomprising a mandrel having formed thereon a plurality of arcuate seatseach generated about an independentaxis eccentric to the axis of themandrel, means carried by the mandrel circumferentially thereof anddefining the lateral limits of the bearing shoe seats, said arcuateseats being coincident to the segmental shoes bearing surfaces, andmeans encircling the bearing shoes and mandrel for securing said shoesto the mandrel, comprising a clamping screw for each end of the shoes.

9. A mandrel for supporting a plurality of segmental bearing shoes whilehaving the arcuate 4 bearing face on the contact rib thereof formedcomprising a mandrel having formed thereon a plurality of arcuate seatseach generated about an independent axis eccentric to the axis of themandrel, means carried by the mandrel circumferentially thereof anddefining the lateral limits of the bearing shoe seats, said arcuateseats being coincident to the segmental shoes bearing surfaces, meansencircling the bearing shoes and mandrel for securing said shoes to themandrel, comprising a clamping screw for each endof the'shoes, and apair of rings, one for each end of the shoes and supporting the clampingscrews at said ends of the shoes.

ALBERT a. mm.

